It is known to provide a full complement of balls in the grooved raceways of the inner and outer metallic rings of bearings by splitting and expanding the outer ring and assembling the balls between the raceways without a cage. In order to split the outer ring, it is known from U.S. Pat. No. 2,702,216 to score the outer ring on its outer periphery. From U.S. Pat. No. 3,858,288 it is known to provide a radial passage at least partly through the thickness of the ring or a score in one end face of the ring. Such measures produce a weakened or relieved zone such that when the ring is exposed to sufficient force it fractures along an axial plane defined by said zone. During fabrication, the adapted outer ring would be formed in conventional manner, hardened by heat treatment and then fractured in a jig to ensure the ring is not distorted prior to final assembly.
Problems arise in the fabrication of split bearing rings by conventional methods. Particularly, unless the ring cracks cleanly there is a danger that small loose metallic particles could be created which could become detached and enter the bearing surfaces with adverse effects. A general object of the present invention is to provide an improved bearing ring adapted to be fractured and an improved method of making such a ring.